1. Field of the Invention
The present invention relates to a method of producing superconducting ceramic wire. More particularly, it relates to a method of producing a superconducting ceramic wire from a metallic oxide glass material obtained by melt-quenching a metal oxide-forming chemical composition capable of being converted into a superconducting ceramic.
2. Description of the Prior Art
The production of superconducting ceramic wire has been thought to be very difficult due to the brittleness of the material. Hitherto, the wire is barely produced by so-called "noble metal-sheathed drawing method" in which a superconducting oxides composition is preliminarily sintered, packed in a noble metal sheath or pipe such as silver in a fine pulverized form, and then subjected to cold working to form a drawn wire of the sintered material, followed by a heat treatment to give a superconducting wire. In this method, the pipe may, if possible, be removed by dissolving with chemicals.
According to the above method, the use of the noble metal pipe is not only costly but also restricts the length of the resulting wire. Further, the continuity of the sintered powder is liable to break during the cold working, making wire-working difficult and causing poor flexibility in the resulting wire. Further more, the cover of the noble metal is liable to limit the supply of oxygen during the heat treatment, which has an important role in preparing superconducting ceramics.